The correct answer is B: Operators may operate after 30 days, providing they have not been told that their station is within 1 kilometer of PLC systems using those frequencies. How long an operator must wait after filing a notification with the Utilities Technology Council (UTC) before operating on the 2200-meter or 630-meter band is that operators may operate after 30 days, providing they have not been told that their station is within 1 kilometer of PLC systems using those frequencies. There's a 30-day waiting period unless notified of proximity to PLC systems. For amateur radio operators, this is important for low-band operation. Understanding this helps ensure legal operation.